YMCA Lifeguard Practice Test 2025 - Free Lifeguard Questions and Study Guide

The device that analyzes a victim's heart rhythm and provides an electrical shock to the heart is the automated external defibrillator (AED). AEDs are designed to be user-friendly and automatically assess whether a person is experiencing a life-threatening heart rhythm, such as ventricular fibrillation. When necessary, the AED administers a shock to restore a normal heart rhythm.

AEDs are widely used in emergency situations, particularly because they can be operated by laypersons with minimal training. They provide spoken prompts and visual instructions to guide users through the process of delivering a shock, making them an essential tool in scenarios like cardiac arrests.

In contrast, a pacemaker is a device that helps regulate the heart's rhythm in individuals with specific heart conditions but does not provide shocks for resuscitation. An aerobic defibrillator is not a recognized term in medical devices, and a cardiac monitor is typically used to observe heart rhythms and other vital signs in a clinical setting, without the capability to deliver shocks to the heart.